This invention is in the field of ovens used for shrink wrapping. A common application of this technique utilizes pre-formed polyethylene bags with a film thickness in the range of 0.002 to 0.012 inch that are put over goods stacked on a pallet. The pallet is then placed in the oven to heat the polyethylene to its shrink temperature in the range of 190 degrees to 300 degrees Fahrenheit. At this temperature the bag shrinks, conforming to the shape of the load and setting up a shrink tension that locks the load securely to itself and to the pallet.